Alarm device



1,488,861 H. BROWN ALARM DEVICE v April 1 1924.

Filed Oct. 5, 1922 Ilill.

- wuewtoz Harold rawn.

TES

HAROLD BROWIZI', OF KANSAS CITY, KANSAS.

ALARM DEVICE.

Application led October 5, 1822. Serial No. 592,596.

To all whom t may concern:

Be it known that I, HAROLD BROWN, a citizen of the United States, residing at Kansas City, in the county of Wyandotte and State of Kansas, have invented certain new and useful Improvements in Alarm Devices; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as willl enable others skilled in the art to which it appertains to make and use the same.

rlhis invention relates to an improvement in signal and alarm devices for pneumatic tires adapted to indicate the pressure of air within the tire by the movement of a pointer over suitable indicia and also to audibly sound `an alarm when the pressure in the tire falls to a predetermined point.

The object oiE the present invention is to provide an improved and simplified instrument of the character indicated providing means for adjusting the same and further providing means insuring the positive and accurate operation of the indicating means.

rl`he invention consists in the novel construction,'arrangement and combination of parts as hereinafter more particularly described and claimed. j K

@ne sheet of drawing accompanies this specilication as part thereof, in which like reference characters indicate similar parts throughout. f

Figure 1 is a side elevation of an improved device;

llig. 2 is a vertical sectional view;

Fig. 3 is a horizontal transverse section taken on the line 3-3 oi' Fig. 2;

Fig. l is a detail elevation view of the `actuating plunger, and

, Fig. 5 is a fragmentary vertical sectional view of a modiiedvform of housing.

. ln accordance with my present invention, a body member 1 is provided with a bore 2 enlarged and threaded adjacent one end as at 3 yto permit the screwing of the same on the nipple ci a pneumatic tire, a gasket Zlbeing preferably provided at the base of the threadedbore 3 as indicated. A smaller bore 5 provides a passage between the bore 1 and an internally threaded core 7 provided' on thejother end of .the member. AAn elastic diaphragme is adapted to be seated( in the bottom of bore Tte be operated upon by the pressure of air in the bore 5. A second member or housing 8 exteriorly threaded adjacent one end to seat within the bore 7 is provided with a longitudinally extending bore 9 which is provided with a groove 10. A plunger 11 seats in bore 9 and is provided with a key 10 slidable in groove 10 to prevent rotation of the plunger. Plunger 11 is provided with a tubular eX- tension 12 which is formed with a spiral slot 13. A rod 14 provided adjacent its lower end with a radially extending pin 15 llits within tubular extension 12 with the pin 15 slidable in slot 13. The housing 8 is provided with an internally threaded bore 23 adjacent its top end in which is mounted a spiral spring 24.- secured to the rodll as upon pin 26 and to the housing 8 as `upon pin 25. An eXteriorly threaded plug 27 is adapted to seat in bore 23 and has upon its lower face a radially extending recess or slot 28 adapted to receive, at predetermined times, av similarly extending pin 29 fitted to rod 14. rlhe upper end of the rod 14 is bent as at 16 into a crank and carries, as by lug 19, a freely hanging metal ball 20. At its upper end rod 14C is threaded as at 17 and is adapted to carry bell housing 21 secured thereon as by a nut 18. Housing 8 is provided adjacent its upper face with an annular groove 22 providing a seat for the lower edge of bell member 21. A coil spring 30 seats against plunger 11 and the medial wall of housing S and exerts a downward pressure upon plunger 11 against the diaphragm 6. Air is admitted to the bore 5 through a transverse bore 31 in housing l having an enlarged internallythreaded portion 32 adapted to receive the eXteriorly threaded nipplepart of a conventional tire valve 33. lt desired, the housing or body 1 may be provided with a spider 34 carrying a downwardly projecting stem as is illustrated in Fig. 5, spider 34: being seated at the top of bore 3 by means of which arrangement the device can be secured to an ordinary tire nipple without removing the valve, stem 35 operating to open the valve upon the seating ofthe alarm device.

The bell 21 is securely fixed to rod 14: and is provided on its outer face adjacent its lower edge with a pointer fadapted to invdicate in association with suitably marked indicia V37 provided upon the lace of the housingB, the amount of pressure in the tire as indicated by the rotation of rod 14: and the bell member 21. y c

The operation of the device will now be described: Y Y. j

When the tire has beenliniated o the ro er pressure, say to eig ity poun s per gquire inch, which pressure will be indicated on the device as shown in F ig. 1, the pressure re-acting against the diaphragm 6 tends to force the same upward into the bore 9. Inasmuch as the plunger 11 is seated on the diaphragm the plunger will be responsive to movements of the diaphragm, it being remembered that the plunger 11 is held against turning movement by means of its pin 10. It will also be remembered that the rod or spindle 14 is provided with a radially extending pin 29 intermediate its ends, this pin being disposed below the plug 27. The rod 14 may therefore be rotated about its axis but may not be moved upward with respect to the plug 27 except at the point where the said pin 29 is in alignment with the recess or slot 28 in the said plug. Under normal conditions the pin 29 is not seated in the recess 28, and, therefore, rod 14 may be turned in one direction or another as movement is imparted to the plunger 11 within the bore 9. When the plunger 11 moves upwardly the rod 14 will rotate in a clockwise direction, and in a counter clockwise 'direction when the plunger moves downward.

At this point it may be stated that Fig. 2 shows the position of the parts when there is no pressure whatsoever acting against the diaphragm 6 and that the diaphragm 6, being of soft rubber, will stretch suiiiciently to impart the necessary range of movement to the plunger 11 within the bore 9. It will also be recalled that the rim of the bell 21 normally contacts with the upper end of the body 8 and, consequently,

will not vibrate. Removal or separation of the bell rim from the body 8 is eiected when the pin 29, carried by the rod 14, enters the recess 28 in the plug 27. Just how this operation takes place will now be described.

The rod or spindle 14 is Vadapted to be turned suiciently to allow the pin 29, carried thereby, to play on either side of the recess 28, in the plug 27. As the pressure in the tire is increased from Zero to eighty pounds (which, for the purpose of this case, is assumed the normal iniiation pressure of the tire). For the purposes of this case, it will also be assumed that the tire alarm will function when the pressure in the tire stands at forty pounds. When the inflation of the tire has reached forty pounds, the pin 29, on the spindle 14, will have moved in a clockwise direction toward the recess 28, and

will have entered said recess when the pressure reached forty pounds. Upon the pin 29 entering the recess the spindle, and the bell 21 carried thereby, will also move upwardly, this upward movement being given by the spring 24, which is tensioned to effect such movement. To disengage the pin 29 from the recess 28, in order to allow further clockwise rotational movement to be imparted to the rod 14, it becomes necessary to manually press downward on the rod 14. Thereafter rotational movement of the pin 29, continues on the further side of the recess 28, until the Vdesired degree of pressure has been obtained within the tire.

Reduction, as by puncture or leakage, will cause a reverse movement in the mechanism until the pin 29 becomes seated in the recess 28, at which time, as has already been explained, the rim 21 of the bell is removed from contact with the body 8, and is thereiore in a position to vibrate when struck by the clapper 20.

lf it is desired to have the device signal at a point higher or lower than that indicated, namely 40 pounds, this may be eiected by increasing ordecreasing the stiffness of the spring 30 within the bore 9; this for the reason that a sti'er spring will require a greater pressure to move the plunger 1l upwardly a given distance, and hence the pin 29 will not register with the recess 28 except at a higher pressure. The same ob ject may be accomplished by varying the relative positions of the pin 29 and recess 28, as by turning the plug 27, with respect to the housing 8.

Having thus fully described my invention, l claim:

1. In a device for indicating tire pressure, the combination of a body having a cylindrical chamber, a plunger movable in said chamber, a spring within the chamber tending to eject the plunger therefrom, a diaphragm closing the exit end of the chamber and against which the plunger normally seats, a spindle extending into the cylindrical chamber, means between the spindle and plunger for imparting rotary movement to the spindle as translatory movement is imparted to the plunger, a convolute spring having one terminal aiiixed to the spindle and the other terminal aiiixed to the said body, a disc adjustably secured to the said body above the convolute spring, said disc having a central opening through which the spindle passes and having a radial recess on its under1 side, a radial projection carried by the spindle which may enter the said recess when aligned therewith, a bell member carried by the spindle and normally having its rim in contact with the said body, except when the radial projection on the spindle is entered into the recess in said disc, and means confined within the bell member for freely striking same.

2. In a device for indicating tire pressure, the combination with two distinct members one of which is a cup-like member and the other of which has a chamber, of a diaphragm closing one end of said chamber, a spindle to one end of which the cup-like member is aixed and the other end of which projects into the said chamber a clapper Within the cup-like member, and means for causing displacement between the two said members When the diaphragm is iieXed to a certain degree, said means including mechanism for imparting turning movement to the spindle as the diaphragm is flexed.

3. In a device for indicating tire pressure, the combination with two distinct membersJ one of Which is a cup-lile member and the other of which is a chamber, said members being normally in contiguous relation, of a diaphragm closing one end of said chamber, a spindle to one end of which the cup-like member is affixed andthe other end ofvvhich projects into said chamber, means between the diaphragm and spindle imparting rotary movement to the latter as the diaphragm is flexed, means permitting outward movement of the spindle at a given point in its rotation to eiiect separation of the said members, and means for restraining the spindle at a given point.

4. In a device of the character described having a freely vibrating` clapper and a gong adapted to be rotated, seated and unseated in response to variations in pressure in the tire, operative means for said gong comprising a supporting spindle secured thereto, a plunger operated bythe pressure of the air having a bore in which an end of the spindle seats, said plunger provided with a helical slot surrounding the bore to guide a pin projecting therein from the spindle,

and a 'thrust bearing for the spindle, said thrust bearing including means for permit# ting a predetermined longitudinal movement to the spindle at a predetermined point in its rotation.

5. In a device of the character described having a freely vibrating clapper and a gon adapted to be rotated, seated and unseate in response to variations in pressure in the tire, operative means for said gong comprising a supporting spindle secured thereto, spring means operative to rotate the spindle in one direc-tion, a spring controlled plunfer operated by the pressure of air and having a bore in which one end of the spindle seats, said plunger provided With a helical slot surrounding the bore to guide a pin projecting therein from the spindle, and an adjustable thrust bearing for the spindle inc-luding means for permitting a predetermined longitudinal movement to the spindle at a predetermined point in its rotation.

6. The combination with a body member adapted to be connected with the air nipple of an automobile tire, of a bell member at one end of said body member, a scale and pointer at the peripheral edge of the respective members, and means Within the body member responsive to variations in tire pressure, said means including a spindle connected to the bell member and adapted to rotate the latter when acted upon by the pressure-responsive means. j

In testimony vvhereof I ax my signature.

HAROLD BROWN. 

